Preparation of sponge of these high-melting-point high-toughness metals is presently effected by using a reaction apparatus comprising a reaction chamber which can be tightly sealed and heated and a condensation chamber provided above the reaction chamber, and which can be cooled and evacuated. Using such an apparatus, a metal chloride (titanium tetrachloride for instance) is reacted with an active metal (magnesium, for instance) in the reaction chamber, whereafter the produced spongy metal is separated from the unreacted active metal and the chloride of the active metal, the latter two being removed by evacuation, and finally recovering the active metal chloride and the active metal in the condensation chamber.
Such an apparatus is, for instance, disclosed in Japanese Laying-Open Patent Publication No. 18717/72. In the apparatuses of this kind, it is a problem how to seal off the upper condensation chamber from the lower reaction chamber. In the apparatus of this laying-open patent publication, the passage of the intermediate connecting section connecting the reaction chamber and the condensation chamber is closed by a partition. But such a partition is defective not only in that it has a complicated structure but in that it gradually deforms suffering from thermal strain, resulting in imperfect closure.
Japanese Laying-Open Patent Publication No. 49922/77 discloses a similar apparatus in which the above-mentioned defect is partially eliminated. In this apparatus, the intermediate connecting section is closed during the reaction period by a lid of a fusible metal such as magnesium, aluminum, zinc, antimony, etc., which is fixed by means of bolts. And prior to the period of vacuum separation, the lid is removed by melting it by means of a suitably provided heating means, so that communication between the two chambers are restored. Although this apparatus eliminates the above-mentioned defect, it requires that a new lid with a smoothly finished plane surface must be prepared for each run. Therefore, this apparatus is not entirely satisfactory from the viewpoint of operation convenience and economy.
In the two apparatuses mentioned above are difficult in separating the reaction chamber at a high temperature and the condensation chamber. Therefore the reaction chamber must be hoisted together with the condensation chamber by means of a crane or the like when it is removed from the heating apparatus. Under the current circumstances that a larger capacity of a batch is being demanded, the above-mentioned inconvenience will be intensified.
It is the object of this invention to overcome the defects of the above-mentioned prior art apparatuses for reduction of chlorides of high-melting-point high-toughness metals comprising a reaction chamber and a condensation chamber connected together by means of an intermediate connecting section and to improve the function thereof by employing a seal pot structure in the connecting section as the closing means.